The phrase "groundwater table" refers to the level at which water sits underground. It represents the depth at which you would find water if you were to dig a hole in the ground. Full definition
Though growing seasons in some areas will expand, the combined impacts of drought, severe weather, lack of accumulated snowmelt, greater number and diversity of pests, lower groundwater tables and a loss of arable land could cause severe crop failures and livestock shortages worldwide. (livescience.com)
Exacerbating the problem are a rapidly retreating groundwater table in the north (Science, 18 June 2010, p. 1462) and pollution of major waterways. (sciencemag.org)
Another interpretation is that, beyond fossil - carbon waste, the EF is a poor representation of how well we are managing the planet, because a wide range of studies indicate that harm to Earth's ecosystem services is already significant, including declining soil fertility, increasing water scarcity, lowering of groundwater tables, oft - depleted fisheries, and loss of evolutionary history through species and population extinctions [22]--[26]. (journals.plos.org)